This invention relates to a disposable syringe wherein two incompatible materials are contained in separate vials until prior to usage. More particularly, it relates to a disposable syringe wherein one vial is received in the syringe body which also accommodates a double-pointed cannula having a hub member and a second vial is retained by an adapter which fits over the outside of the syringe barrel to provide upon movement of the adapter over the syringe barrel fluid communication between the two vials and intermixing of the two components.
Many types of disposable mixing syringes containing a dry medicament and a solvent for it are currently available. However, many such units are expensive to manufacture in that they require a multiplicity of parts and/or require several manipulations of the components in order to afford thorough mixing of the medicament with the solvent. In U.S. Pat. Nos. 3,327,710; 3,336,924; 3,397,694; 3,542,023; 3,636,950 and 3,659,602 syringes of the type concerned with in this invention are disclosed in that they utilize a separately attached vial for intermixing through a cannula which is to be later utilized as the means for hypodermic injection or a two-vial system wherein the contents of both vials are consolidated into one and then the one vial utilized as a hypodermic syringe. U.S. Pat. Nos. 3,327,710; 3,336,924 and 3,397,694 indicate syringe systems wherein the contents of an externally disposed vial are emptied into and mixed with the contents of a syringe. These systems are costly to manufacture and do not always provide proper sealing and subsequent communication with the vials because of the types of piercing of a stopper or the removal of a plug member to provide the necessary communication. The same problems with multi-component parts and positive piercing can be seen in the disposable cartridge for admixing with two components in U.S. Pat. No. 3,636,950. In U.S. Pat. Nos. 3,542,023 and 3,659,602 double vial systems are indicated for usage in a two-component syringe. However, these units do not lend themselves to a prepackaged and preloaded syringe system in that the adapter for the second vial extends outwardly a substantial distance from the syringe and subsequently when the second vial is attached, the system is awkward to handle and requires the manipulation of several components. Further, cost considerations are involved in special molding techniques for the specially designed post as in the 3,659,602 patent or the manipulation of several components to afford positive puncture of the two vials as in the 3,542,023 unit.
It is an advantage of the present invention to afford a novel syringe for mixing of a dry and a fluid component prior to usage with a minimum manipulation of steps and components. Other advantages are a double vial syringe unit which will afford maximum sealing of the two component materials from each other, positive puncture of the two vial stoppers with movement of one vial toward the other, preassembly of the two vials prior to usage and in a compact manner which will permit ease in packaging and a syringe unit which is easy to fabricate from a molding standpoint and thus less costly to manufacture which therefore lends itself to being disposable.